Fibroblasts are the major cell type responsible for the synthesis of collagen, a fibrous protein essential for maintaining the integrity of the extracellular matrix found in the dermis of the skin and other connective tissues. The production of collagen is a finely regulated process, and its disturbance may lead to the development of tissue fibrosis. The formation of fibrous tissue is part of the normal healing process after injury, including injury due to surgery. However, in some circumstances there is an abnormal accumulation of fibrous material such that it interferes with the normal function of the affected tissue.
Scar tissue serves only a structural role, but does not contribute to the function of the organ in which it appears. For example, in carpal tunnel syndrome, fibrosis scar tissue and/or swelling in or around the tendon sheaths that pass through the carpal tunnel can pressure on the medial nerve causing pain and numbness in the fingers.
Fibrotic growth can proliferate and invade healthy surrounding tissue, even after the original injury heals. In most cases fibrosis is a reactive process, and several different factors can apparently modulate the pathways leading to tissue fibrosis. Such factors include the early inflammatory responses, local increase in fibroblast cell populations, modulation of the synthetic function of fibroblasts, and altered regulation of the biosynthesis and degradation of collagen.
Stimulation of fibroblast activity is involved in the development of fibrotic conditions, including spontaneous and induced conditions. Abnormal accumulation of collagen in the extracellular matrix, resulting from excessive fibroblast proliferation and/or collagen production, can cause fibrosis of a number of tissues including the skin. Many common debilitating diseases, such as liver cirrhosis and pulmonary fibrosis, involve the proliferation of fibrous tissue as do certain skin diseases such as scleroderma, and the formation of adhesions, keloids, and hypertrophic scars.
Conventional treatment of most fibrosis frequently involves the administration of corticosteroids, such as prednisone, and/or other medications that suppress the body's immune system. The goal of current treatment regimens is to decrease inflammation and subsequent scarring. Responses to currently available treatments are variable, and the toxicity and side effects associated with these treatments can be serious. Indeed, few patients respond to corticosteroids alone, and immune suppression medications are often used in combination with corticosteroids.
Thus, there is a need to develop new devices and methods to treat fibrosis that allow accurate and precise implantation of the device at, near, or in the fibrous tissue resulting in minimal physical and psychological trauma to the patient.